Ceramic disc tube socket



Dec. 20, 1960 A. A. SINDELAR CERAMIC DISC TUBE. SOCKET Filed Jan. 4, 1957 IN VEN TOR. A RNO A. SINOELAR BY .4 r TORNE vs United States Patent N CERAMIC DISC TUBE SOCKET Filed Jan. 4, 1957, Ser. No. 632,439

2 Claims. (Cl. 339-176) v This invention relates to ceramic disc tubes and more particularly to a socket therefor.

Recent developments in the electron tube art have brought about the existence of ceramic disc tubes. These tubes are planar element tubes having ceramic discs for insulation between the disc-like terminal contacts of the tubes. The ceramic disc tubes presently available are small and especially adaptable to very high frequency use. As a consequence, simple circuit-to-tube connectors must be available for effective connection to the tube with a minimum of disturbance on the circuit.

It is an object of the invention to provide a small,

lightweight, simple-to-manufacture socket useable with planar element tubes such as the ceramic disc tube.

' It is a feature of the invention that the elements used in manufacture of the socket are readily formed of sheet materials, yet provide sure contact with a simple construction.

Further objects, features, and advantages of the invention will become apparent from the following description and claims when read in conjunction with the drawing in which:

The figure shows an isometric view of the invention.

In the figure a socket assembly is shown for push-pull use of a pair of disc tubes, with one tube inserted into one side of the socket for illustration of the relation of thetube to the socket.

Briefly stated, the disc tube consists of a plate contact 10, a grid contact 11, and cathode contact 12 which are cylindrical, coaxial, and in adjacent parallel planes. At the end of the tube opposite the plate contact, which is bare at the end, are two heater terminals also bare at the end. Only one heater contact 13 is visible. These heater contacts are small buttons protruding from the ceramic disc insulator 14. Other ceramic discs 15 are used as insulators between the plate grid and cathode contact cylinders. The tube itself is merely a form of the coplanar disc tube which may have more contact cylinders or may take slightly different shapes or forms which are yet adaptable to use with the invention. The term coplanar disc tube is used for reference to the numerous forms to which this type of tube may take.

The socket assembly shown, in view of the heater contacts, is quite readily adaptable to a push-pull array of a pair of tubes in an amplifier circuit. Accordingly, the invention is illustrated with this form. The corresponding parts between the sides of the sockets which are identical are numbered the same. Thus, plate contact 20 is the same stamping and is inserted at either end of the insulator board 21. Intermediate contact members, such as the grid contact member 22 and cathode contact member 23, are of the same shape and are merely repetitions of one another. The heater contact terminals are comprised of two stampings, 24 and 25, which are mounted together in a single slot on insulator 21 and thus maintained at the same voltage. The other terminal pair 26 is identical to terminals 24 and 25 but is turned around relative to insulator board 21.

2,965,873 Patented Dec. 20, 1960 ICC Insulator board 21 is a slotted, relatively thin and long piece of insulation. Insulator 21 must be relatively rigid and have the desired electrical characteristics for the frequencies involved. These slots 30 are similar along the edge of the board from either side and, in the model used, extend approximately one-third of the board width into the edge. The slots are spaced approximately equidistantly but are spaced in accord with the contacts of the tube in order to align the terminals with the tube contacts.

Plate terminal 20 is fashioned from a fiat plate left in its original form at portion 31. The terminal portion touching the tube is a strap which is narrowed down in width from the original width at 31 and bent over into a relatively narrow U-shaped strap 32. The U-shape extends along the length of the original piece. The upper portion of this strap, which first meets the plate contact, is curved so as to facilitate entry of the tube into the socket. The lower portion is somewhat straight, with a slight angle in toward the volume of the socket containing the tube, so as to ensure a springy or elastic contact.

Theother end of the original strap 31 terminates in a bifurcated form extending downward toward the insulator 21 from the original shape 31. Thus, two tabs 33 and 34 are formed which are spaced the width between slots both across and along the insulator board. The portion of the prongs extending below the insulator board are twisted slightly to lock the terminal onto the board. Since the tabs 33 and 34 are spaced along the board, and rest on it, considerable rigidity longitudinally of the board is given to this terminal so as to make the springiness of strap 32 more effective in contacting the plate contact 10 of the coplanar disc tube. Of course, the two tabs at opposite edges of the insulator provide rigidity transverse of the insulator.

As stated before, the grid and cathode terminals 22 and 23 are substantially alike. The original stock of terminal 23, of thin, wide, and fairly long material, has cut into one end of it a deep U 35 of almost the full width of the stock material. The width of the U is substantially the same size as the contacts 11 and 12 of the coplanar disc tube. The bottom of the opening is of about the same radius as the contacts of the tube. Just above the resting point of the inserted tube the remaining prongs are slightly thicker inwardly at 29 to retain the tube in the socket. The thickness of the stock material is slightly less than the thickness of the contacts in longitudinal dimension of the tube so as to enter between the insulator discs 15 and 14 without difficulty.

The other end of the stock material is also bifurcated by being cut into a pair of tabs which are inserted through their slots in insulator 21. As with the plate terminal 20, the ends of the tabs below the terminal board are twisted slightly to lock the contac tor into place. The width of the opening 35 in the fingers is slightly elastic so as to provide a firm, springy meeting with the contact discs of the tube, and with the narrower portion at 29 provide a retention of the tube.

The heater terminals for a tube on one side comprise an unlike pair positioned in two different sets of slots. In one slot will be found a flat L-shaped piece 24 and a bent L-shaped piece 25. The fiat piece has an upper portion bent over slightly at 36 to facilitate entry of the tube into the socket area. At a point opposite the ultimate resting point of the contact pins 13 of the tube is a recessed dimple 37. The bottom of the L extending along the transverse dimension of the insulating board is bifurcated, creating a pair of tabs which extend through slots to below the terminal board. The bent L-shaped terminal 25 is originally of a slightly longer stock and is bent into a broad open Z-shape, looking transversely at the socket, so as to position the upstanding part 38 i of the L parallel to and in the same plane as that of the'unbent L 24. The upstanding portion 38 is now above the unbent L of the adjacent slot. The remainder of the shape of the bent L is the same as the unbent L including the bent-over tip and the dimple recessed to receive the contact pins 13 of the tube. The other terminal pair 26 is identical in form, but in its insertion into the adjacent slot is turned one hundred and eighty degrees relative to the longitudinal axis of the socket. The relation of the bent terminal 25 and the far unbent L-shape, which both are incontactwith the inserted tube, is the same as that of the near pair.

It is readily obvious that this socket-maybe built integrally with a printed circuit board .merely by punching the necessary holes or slots therein and assembling,

the terminals illustrated in the manner described. Thus the coplanar disc tube is mounted closely adjacent the pertinent circuitry with minimum lead length and in a manner consonant with the latest available circuit techniques.

Although this invention has been described with re spect to particular embodiments thereof, it is not to 'be so limited because changes and modifications may be made therein which are within the full intended scope of the invention as defined by the appended claims.

Iclaim:

1. A tube socket for disc tubes comprising, a base and a plurality of contacts, said base comprising aflat strip of insulating material having substantially parallel side edges and pairs of transverse slots disposed longitudinally along said strip, one slot of each of said pairs being aligned with the other slot .in the opposite side edge of said strip, the spacing between pairs corresponding to the spacing between disc terminals of one of said tubes that is to be mounted, a pair of end contacts and a plurality of intermediate contacts fabricated from fiat conducting material, each of said contacts having tabs that extend from one end thereof and enter respective end pairs of said slots for mountingsaid contacts approximately normal to said base, each of said end contacts having a transverse face for contacting end contacts of said tube, each of said intermediate contacts having a pair of prongs extending from the end opposite said respective tabs, said prongs being spaced transversely with respect to the side edges of said base and being adapted for-receiving and contacting the edges of disc elements in said tube, and the tabs of each of said intermediate contacts entering a-respectivepairof said slots that is intermediate said end pairs.

2. A tube socket for receiving disc tubes comprising, a flat insulating base having a plurality of pairs of slots, said pairs being disposed along a central line that determines the direction of the axisofa tube as it is mounted in said socket, each of said pairs of slots being aligned and disposed on'opposite'sides of said central line, said pairs being spaced along saidrcentral line to correspond to the spacing of disc terminals that are on said tube, first, second, third and fourth conducting terminals mounted alongsaid central line insaid slots and in the order named, each of saidterminals'being mounted transversely with respect to said 'line and approximately normal to said base on one side thereof, said first terminal being substantially flat and L-shaped, one leg of said first terminal being adjacent to said base and having tabs extending therefrom into a first one of said pairs of slots, said second terminal being approximately L-shaped transversely to said central line, one leg of said second terminal being adjacent to said -base an'd having tabs extending therefrom into a second pair of said slots adjacent said first pair, the other legs of said first and .second terminals being approximately normal to said base, said other leg of said second'terminal being offset so that part thereof is in thesameplane'as said other leg of said first terminal, said other legs being on Opposite sides of a normal plane through 'said central line, said third terminal having tabs extending from one end thereof and entering intermediateoncs of'said pairs of slots and having a pair of spaced extending prongs on the other end adapted to receive disc contacts of said tube and to contact the edge thereof at diametrically opposite points, and a fourth terminal comprising a contacting portion with a transverse face approximately normal to said base and U-shaped in cross sections, one end of said U-shaped portion having tabs extending therefrom and entering respective ones of said slots.

References Cited in the file of this patent UNITED STATES PATENTS 2,636,067 .Kraft Apr. 21, 1953 

